Stability of gold nanowires at large Au-Au separations

TL;DR

This paper explains the stability of gold nanowires at large separations by showing that light atoms like hydrogen stabilize the structures through charge transfer, resolving previous theoretical and experimental discrepancies.

Contribution

It reveals that light atoms, especially hydrogen, stabilize gold nanowires at large separations via charge transfer, a novel insight from first-principles calculations.

Findings

Hydrogen atoms stabilize gold nanowires at large separations.

Charge transfer from gold to light atoms enhances cohesion.

The study resolves a long-standing controversy in nanowire stability.

Abstract

The unusual structural stability of gold nanowires at large separations of gold atoms is explained from first-principles quantum mechanical calculations. We show that undetected light atoms, in particular hydrogen, stabilize the experimentally observed structures, which would be unstable in pure gold wires. The enhanced cohesion is due to the partial charge transfer from gold to the light atoms. This finding should resolve a long-standing controversy between theoretical predictions and experimental observations.